In today's modern metropolis, the mythical beasts from the 'Classic of Mountains and Seas' never vanished—they've long infiltrated human society in disguise.
Jiang Ye, a community grid officer, is recruited into the top-secret agency 'Shanhai Bureau.' On his first day, he accidentally activates the ancient artifact 'Shanhai Mirror'—and suddenly gains the power to see through monsters' human facades. His blood runs cold: every neighbor he's known and chatted with daily? All legendary Shanhai beasts.